Subject: Re: [PATCH] refs: add missing remove_on_disk implementation for debug backend

From: Patrick Steinhardt <[email-masked]>
Date: Fri, 24 Oct 2025 11:11:27 +0200

On Fri, Oct 24, 2025 at 08:38:14AM +0000, RuanXinyu via GitGitGadget wrote:
> From: RuanXinyu <[email-masked]>
> 
> The debug ref backend (refs_be_debug) was missing the remove_on_disk
> function pointer, which caused a segmentation fault when running
> 'GIT_TRACE_REFS=1 git refs migrate --ref-format=reftable' commands.

Heh, funny, just as I said nobody uses this infra you show up :) Good
way to prove me wrong, thanks!

> Signed-off-by: Xinyu Ruan <[email-masked]>

Tiny nit: typically, the author and DCO should match. But the autor is
"RuanXinyu" whereas the DCO says "Xinyu Ruan". I don't really think that
this is something that warrants a new version, but I wanted to point
this out anyway so that you can fix this going forward.

> diff --git a/refs/debug.c b/refs/debug.c
> index da300efaf3..dd49080836 100644
> --- a/refs/debug.c
> +++ b/refs/debug.c
> @@ -48,6 +48,14 @@ static int debug_create_on_disk(struct ref_store *refs, int flags, struct strbuf
>  	return res;
>  }
>  
> +static int debug_remove_on_disk(struct ref_store *refs, struct strbuf *err)
> +{
> +	struct debug_ref_store *drefs = (struct debug_ref_store *)refs;
> +	int res = drefs->refs->be->remove_on_disk(drefs->refs, err);
> +	trace_printf_key(&trace_refs, "remove_on_disk: %d\n", res);
> +	return res;
> +}
> +
>  static int debug_transaction_prepare(struct ref_store *refs,
>  				     struct ref_transaction *transaction,
>  				     struct strbuf *err)
> @@ -432,6 +440,7 @@ struct ref_storage_be refs_be_debug = {
>  	.init = NULL,
>  	.release = debug_release,
>  	.create_on_disk = debug_create_on_disk,
> +	.remove_on_disk = debug_remove_on_disk,
>  
>  	/*
>  	 * None of these should be NULL. If the "files" backend (in

Yup, the implementation looks obviously correct to me. Thanks for fixing
this bug!

Patrick